Power-transmitting device.



E. D. WEEKS.

POWER TRANSMITTING DEVICE.

APPLICATION FILED MA11.2. 1911.

Peteneed Feb. 8, 1916.

\\ g n Q WITNESSES: 1NvEN10R $5 ATTORNEY.:

nnrrnla? srAfrEs 'PATENT ornion.

Finnois D. wEEKs, orisALinA, coLonnDo,;-Ass1e1vo1troTHnoHio a COLORADO sMnLTING a REFINING Co., or DENVER, coronare, `n conrroaATIoN. on

COLORADO.

' PoWER-Tnnnsiviirfrine"DEVICE.

Application filed March 2,V 1911. Serial No. 611,795.. Y

To all whom t may concern.' l v Be it known that I, FRANois -Wnnnaa citizen of the United States residingat Salida, county of Chaffee, State ofGolorado, have invented certain newand useful Improvements Vin Power-Transmitting Devices; and I do hereby declare the following to be. a full, clear, and exact vdescription of the invention, such as` ywill enable others, skilledin the art to which it apppertains to make, and use the same. l f Y Therinvention relates to transmitting de-A vices in which reciprocating or continuous rotary motion is converted into intermittent linear or rotary motion. lin devices here-Y tofore employed for this purpose toothed racks, pawls and ratchets, or similar eSGiLPk. ments were commonly used, with the result that the extent of the intermittent movement could only be varied in fine gradations byemploying very small teeth, in ,consequence ofV which the teeth ,were (correspondingly l`weak. Furthermore such devices were 111-;

herently Vrigid so thatabnormal loads were liableto vcause breakage of important' parts unless those parts were made abnorI-nallyY strong, in which case they were uneconomi cal of material. v y g In accordance with my invention the force is transmitted by frictionalengagement between co-acting surfaces, soy that the load is limited by slipping of the friction surfacesand breakage is avoided, and capacity for minute adjustment throughout a wide range is. afforded. l Y W In the accompanying drawings forming a part of this specification, and illustratingthe preferred embodiment of my invention, Figure lis a front elevation ofthetransmitting device; Fig. 2 is an end elevation vviewed from the driving end; FigLS'is anqend; elevation viewed-from the brake-end;y Fig. 4, is a planview of the drivingj end. 1 The base 1 supports thepedestals2with their bearings 3, through which the shaft l extends. Near the ends o-f the shaftare rigidly mounted the driving pulley and thebrake pulley 6. The driving strap Z exe tends partly around the driving pulley and has a weight 8 suitably fastened to one end, while the other end is connected at 9,l toa lever-frame l0l loosely pivoted on theshaft 4. rIhe brake strap` 1l vextends partly around the, brake pulley, and has the weightv 12y attachedto one end, while theother endris Patented Feb. 8, 1916.;

fastened to the base by means of thev tie rod Y 13 and nut 14 screwed thereon.,- The Arotating Shaft' l5` drives the eccentric/.16 at constant speed. The rod 18 isseoured atene end .to thecollar 17 which inclosesthe eccentrie while the other end-isA screwed into the, turnbuckle 1.9.? The other lend of the turnbucklecarries va rod 20: which` isconnected to the leverl() -througha pin and slot connection-M21.' i n The operation` of the, mechanism illustrated is follows: In this; casethe primary motion to. be converted is. a continuous. ro;

tary motionof 15 .whichvis converted by the eccentric 16- into` a reciprocating motion of f theconnecting imembers18,-` 1 9.' and pu-lley results, whichr imparts a correspond; 1ng-'1novement, clockwise as viewed in Fig 3,to thebrake-pulley 6., The tendency of this movement of the brakefpulley is tolift the weight 12 and release the frictional engagementuof the straprv 11l therewith. This lifting of: thezweight' 12 is very slight, only suflicient'to slack the strapfll,-but iit is suii- ,20; 4Itf-w-ill .be understood', however, that lso vleyr by the weight 8,3and a counter-clock-v wise movement, as viewed in Fig. 2, of the cient t0 Apermit the rotation cfshaft 4 under i the impulse of strap Kon pulley 5. As the rody20 begins to` descend the lever-.frame l1Q f .falls and connection 9 rises, under the pull of:weigh-t` 8, but now strap. 11 is; stretched tight on brake-pulley 6. and' exerts suijcient braking effect thereon to prevent` the reverse movement of shaft 4t, and thejstrap.- f? slips Q-verpul-ley 5.4 y Y. j

The anglez throughwhich they shaft l .is turnedduring each cycle of rotationof the shaft 1,5, may be altered by adjusting the tnrnbnckle y119 on the/,threaded rod 18. It will be applareaIV-it` that by screwingy the turn-f buckle up on the rod, the end of the slot will engage the pin at 2l throughout more of the cycle of rotation of the shaft l5, in consequence of which the shaft 4 will be rotated through a greater angle during each cycle. Similarly, as the vturnbuclrle is screwed down, the angle of movement of shaft 4 will be decreased during each cycle. By this means my device is capable of gradual adjustment throughout a wide range. Furthermore, the start of the intermittent rotary motion of the pulley 5 or shaft 4 relatively to the start of the cycle is altered by adjusting the turnbuckle, since the instant at which theV end of the slot engages the pin at 2l in the upward movement of the vertical arm is advanced by screwing up the turnbuckle and delayed by screwing it down. Also the end of the intermittent rotary motion of the pulley 5 or the'shaft 4 may be altered relatively to a point on the shaft l5 by advancing the eccentric, since the points of the eXtreme throw of the eccentric then occur atdifferent points of the cycle.V

I may mount on the shaft 4, preferably between the pedestals, a pulley (as indicated in dotted lines in Fig. l) to convert the inf termittent rotary motion of shaft 4 into intermittent linear motion in one directionof an endless belt or the like; or the intermittent linear motion produced may be used for any desirable purpose.

It will be understood from the foregoing description of a typical apparatus embodying my invention, that the invention is characterized by' the employment of co-acting friction members interposed between the primary driving shaft 15 and the secondary driven shaft 4, mechanism for oscillating the driving friction member through an arc the extent of which is variable at will, the driven friction member being arranged to move with the driving member in one direction and not in the other, whereby the primary continuous rotary or reciprocating motion is converted into the intermittent rotary or linear motion. It will be apparent that for many purposes the strap 7 and pulley 5 illustrated as constituting the driving and driven friction members may be replaced in the proposed combination by equivalent friction devices of many different forms, and that there may be substituted for the brake strap and pulley any other suitable mechanism for restraining orl removing the driving effect of the driving friction element upon the driven friction element in one direction.

Y What I claim is:

l. In a device for the conversion of motion, the combination of a primary driving mechanism rotating continuously and a secondary lmechanism movable vwith intermittent rotary motion, coacting driving and l driven friction members interposed between and connected respectively to the said continuously moving primary mechanism and the said intermittently moving secondary mechanism, the connection from the primary driving mechanism to the driving friction member including mechanism for converting the movement of said primary driving mechanism into an oscillation of the driving friction member, weighted means independent of the primary driving mechanism for imparting a limited -pressure of engagement to the driving friction member during the advance movement, and mechanism for continuously `holding the driven friction member against movement in the reverse direction, substantially as and for the purpose described.

f 2. In a device for converting continuous rotary motion of a primary driving mechanism into an intermittent rotary movement of a secondary mechanism, co-acting driving and driven friction members interposed between and connected respectively to the said primary and secondary mechanisms, the connection from the primary driving mechanism to the driving friction member including adjustable mechanism for converting the movement of said primary mechanism into an oscillation of variable and predetermined extent of the driving friction member, means independent of the primary driving mechanism for maintaining a substantially constant frictional engagementl of the driving friction member on the driven friction member during the advance movement, and mechanism for holding the driven friction member against movement in the reverse direction, substantially as and for the purpose described.

3. In a device for converting continuous rotary motion of a primary driving mechanism into an intermittent movement of a secondary mechanism, a pulley connected to the secondary mechanism, a flexible strap engaging a part only of the circumference of said pulley, means for imparting a limited and constant pullon said strap, connections from the primary driving mechanism to the strap including mechanism for converting the rotary :movement of said primary driving mechanism into an oscillation of the strap, and means for holding the pulley against movement bythe strap in one direction, substantially as and for the purpose described.

4. In a device for converting continuous rotary motion of a primary driving mechanism into an intermittent rotary movement of a secondary mechanism, a pulley connected to the secondary mechanism, a strap in frictional engagement with said pulley, means for imparting a limited tension to said strap, connections from the primary driving mechanism to the strap including mechanism for converting the rotary movement of said primary driving mechanism into an oscillation of the strap and means said last named strap having a Vtensioning device at one end and being fastened Vat the other end to a fixed support, substantially as and for the purpose described.

5. In a transmitting device of the charac` ter described, a rotatable shaft, a pulley on said shaft, a flat flexiblestrap making a partial turn about said pulley, andin frictional engagement therewith, a weight for imparting a limited tension to said strap and limiting the' grip of the strap on the pulley, a

rock lever pivoted to said shaft to impart an oscillatory motion to said strap, and a second weighted strap for frictionally preventing movement of the pulley on the return swing of said rock lever, substantially asv and for the purpose described.

6. In a transmitting device of the charac-` ter described, a primary rotatable driving shaft, an eccentric on said shaft, a pivoted lever adjustably connected to said eccentric to be oscillated thereby, a second shaft, a

lpulley on said second shaft, a strap on said pulley and connected at one end to the piv- Copies of this patent may be obtained for ve cents each, lay-addressing the Gomm'ssoner of Patents,

oted lever, means for imparting al limited 'tension to said strap andV limiting the fricn tion of said strapon said pulley, and mechanism for preventing the movement of said pulleyby said'strap in one direction, substantially as andfor the purpose described.

7. In a transmitting device of the character'descr'ibed, a primary rotatable driving shaft, an eccentric on said shaft, a pivoted lever, an adjustable slot and pin connection.- 2

between the eccentric andsaid pivotedlever to vary the swing ofV thelever and to vary the time of its swingwith respect to move! ment of the eccentric, Va driven shaft, a pulley on said driven shaft, a Weight, a'strap on said pulley subjected to the constant ypull of said weight, said strap being connected at v one end to the pivotedlever, and stationary gripping mechanism for frictionallyv pre# .venting movement -of said pulley byesai'd lstrap Vin one direction, substantially as described. n Y.

In testimony whereof 1 aftiX my signature, in presence of two witnesses. y

, FRANCIS D. WEEKS.

Witnesses: l i

WILLIAM H. DAVIS, LEON W. RosENrHAL.

Washington, '.D. C. 

